One of the known techniques to supply electric power from an electric vehicle to a house is a power management system as shown in Patent Literature 1 described below. This power management system learns the battery consumption during ordinary travel of the electric vehicle and determines the minimum amount of power to be secured in the electric vehicle based on the learning results. The power management device charges the electric vehicle during late-night hours and supplies electric power from the electric vehicle to the house during other than the late-night hours while leaving the minimum amount of power to be secured.
In the aforementioned power management system, the electric vehicle, which still has the minimum amount of power to be secured, cannot travel with the secured amount of power in emergencies where unexpected travel of the electric vehicle is required. If the charge level is always maintained constant in the light of emergencies in preparation, the electric vehicle cannot supply so much electric power to the house.
Accordingly, the present invention is proposed in the light of the aforementioned circumferences, and an object thereof is to provide a power management device which can supply power from an electric vehicle to a house while securing the situation where the user can move by vehicle in emergencies.